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Old Jan 4, 2008, 12:01 AM   #1
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Here are some examples of what I want to shoot.

http://www.flickr.com/photos/2chicos...7603408561065/
http://www.flickr.com/photos/2chicos...7603404504871/
http://www.flickr.com/photos/2chicos...7603404761984/

All these pictures except for the South Maui Surfer were shot w/ a 40+ year old 300/f5.6 Kilfitt Tele-Kilar. The South Maui Surfer was shot with the DA 50-200. Most of these shots are cropped.

I'm trying to decide whether to get the Bigma now, or to hold out for the DA*300.

Pros Bigma:
- available now.
- 500mm reach.
- wide zoom.

Pros DA*
- weather sealed
- should produce very high quality images (sharp).
- smaller, even w/ TC (right?)
- Much faster, slightly faster w/ TC.

I'm kinda on the fence and am wondering if the Bigma @500 will be sharper than the DA* 300 w/ 1.4TC when cropped.

Also, if I get the DA*, which TC is a better match, the Tamron or Sigma?

Thanks.

--John
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Old Jan 5, 2008, 11:59 AM   #2
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can't really say which will be better since the DA* 300 isn't out yet and no one has any experience with it. the bigma is a fantastic lens and i think would be well suited for the shots you want to take being outdoors and in good light.

i have both 1.4x tc. get the tamron. the sigma doesn't work with many lenses, it mostly only works with the sigma ex dg lineup. something with the way the lens inside the tc is mounted. the tamron on the other hand works with all my lenses.
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Old Jan 6, 2008, 12:54 AM   #3
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ishino wrote:
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can't really say which will be better since the DA* 300 isn't out yet and no one has any experience with it. the bigma is a fantastic lens and i think would be well suited for the shots you want to take being outdoors and in good light.

i have both 1.4x tc. get the tamron. the sigma doesn't work with many lenses, it mostly only works with the sigma ex dg lineup. something with the way the lens inside the tc is mounted. the tamron on the other hand works with all my lenses.
That's good to know....I registered that info for later use. Thanks Ishino!!

Dawg

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Old Jan 6, 2008, 2:04 PM   #4
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john,
for nature i'd probably say the 300+ but for what you're going to be using it for i think you would be more satisfied with abilities of a zoom. the 300/4 will end up a 420/5.6 so there is no speed gain or loss. get the bigma, hopefully locally in case QC is an issue..

roy
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Old Jan 6, 2008, 5:51 PM   #5
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here is a picture of both tele converters. notice how the sigma has a raised element and the tamron is recessed. this design is what prevents the sigma from working on most other lenses.
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Old Jan 6, 2008, 7:50 PM   #6
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Ishino, can you mount the Tamron on a MF lens? I know will not make a MF lens into an AF like the Pentax 1.7x, but I was curious if the A contacts would still work and that there would be no damage to the AF mechanism in the converter.

Thanks,

Tim
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Old Jan 6, 2008, 9:38 PM   #7
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NonEntity1 wrote:
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Ishino, can you mount the Tamron on a MF lens?* I know will not make a MF lens into an AF like the Pentax 1.7x, but I was curious if the A contacts would still work and that there would be no damage to the AF mechanism in the converter.
Hi Tim,

AF TCs will transmit all the info that the camera needs for Auto Exposure (as long as you have the aperture ring set to "A", of course), and will allow you to change aperture settings with the wheel on the body.

With the K series bodies, MF lenses actually work a bit better than AF lenses with the TC (from an SR standpoint) because with an MF, no lens FL info is sent by the lens, forcing SR to be set manually. The TCs only pass the lens FL info on to the body without taking the extra magnification of the TC into account, so on AF lenses, the incorrect FL for SR is set by the (now incorrect)info sent from the lens and passed through the TC, and the manual SR setting is locked out, so you can't do anything about it. I haven't tried it, but you can probably insulate a pin to make this work better.

No damage to the AF mechanism is going to happen because the body sees the combo as an having whatever features the lens mounted has.

Another interesting feature of the Tamron AF F 1.4x is that it has the PZ contacts, so theoretically it will work with SDM lenses. Unfortunately, I don't think that the Pentax lens engineers worked with this aspect -- at least not with my copy of the DA* 50-135. While the lens will eventually focus (using the SDM Motor), I find it hunts excessively, and usually will fail to lock focus the first time, then focus correctly and lock with another shutter half press. Others have said that this is no big deal, but I'm inclined to disagree. . . :?:

Scott
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Old Jan 6, 2008, 10:24 PM   #8
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tried the smc-m 135mm with the tamron tonight. as soon as it is mounted on the body it reads it as a manual focus lens and disables the auto focus. nothing is engaged on the tele converter. 100% safe to use with manual lenses.
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Old Jan 6, 2008, 10:51 PM   #9
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Thanks!

Tim
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Old Jan 8, 2008, 2:40 PM   #10
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Ishino/Roy -- Thanks for the input. I think I'll get the 50-500 and a monopod. I'll be surprised if I'm not tempted by the DA*300 when it's available. --John
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